A number of solutions are already known from the prior art that disclose a gas-tight, liquid-tight or explosion-proof cable bushing.
Documents DE 1490332 A, DE 1490624 A, DE 2156608 A, DE 6947647 U, DE 19520758 A1 and CH 358482, all disclose gas-tight bushings for electrical conductors or cables. In these prior art solutions, the strands of the cables are either stripped of insulation individually and then encapsulated or mechanically compressed with costly structures in the bushing channel. The complicated layout of these solutions results in very high production costs. Even if separation of individual strands with subsequent encapsulation could be used in practice for specific applications, the solution, however, cannot open up the mass production market segment.
Another solution for sealing of a flat conductor relative to a housing wall, for example, a sheet metal wall, is described in EP 1936750 A1. Sealing occurs by means of a soft sealing element through which the conductor is pulled so that it is completely enclosed by the sealing element. A particular shortcoming of this solution is that sufficient sealing of the gas side cannot be guaranteed at high pressure. The high percentage of plastic means that at high temperatures the plastic deforms and the required sealing can no longer be guaranteed. At very high temperatures, as, for example, in the case of an accident in the gas meter, these bushings, are not suitable. Production of these bushings is also very expensive so that this form of cable sealing is not suitable for cost-effective mass production.
DE 19517455 A1 discloses a gas-tight cable gland using a shrinkage tube lined with adhesive. Here again the conductor must be processed individually in demanding fashion, which means high labor expense that leads to high costs in mass production.
Hence there is a desire for a fluid-tight cable bushing for ribbon cable that ensures high temperature stability and gas-tightness at high temperatures. There is an additional desire for a cable bushing usable in explosion-hazardous areas which is also suitable for cost-effective mass production.